The lump-sum distribution you received satisfied her 2017 RMD as well as your 2018 RMD, but because you received it after the end of 2017 your 2017 tax return should have included Form 5329 requesting a waiver of the excess accumulation penalty. See Waiver of tax on the last page of the instructions for 2017 Form 5329 to see how this form needs to be prepared:
https://www.irs.gov/pub/irs-prior/i5329--2017.pdf
As for reporting the distribution, you'll receive a code 4 2018 Form 1099-R near the end of January 2019. Enter this Form 1099-R into 2018 TurboTax under Wages & Income (or Personal Income) -> Retirement Plans and Social Security -> IRA, 401(k), Pension Plan Withdrawals (1099-R). Be sure to then click the Continue button on the Your 1099-R Entries page and indicate that you received all of your RMD for 2018.
